As an important signaling molecule, hydrogen peroxide (H₂O₂) secreted externally by the cells influences cell migration, immunity generation, and cellular communications. Herein, we have developed a microfluidic approach with droplets in combination with Au nanoclusters for the sensitive detection of H₂O₂ secreted by a single cell. Isolated in the ultrasmall volume (4.2 nL) of a microdroplet, single-cell secreted H₂O₂ can initiate dramatic fluorescence changes of horseradish peroxidase–Au nanoclusters. We have demonstrated an ultrahigh sensitivity (200–400 attomole H₂O₂ directly measured from a single cell) with good specificity. It offers a useful research tool to study the cell-to-cell differences of H₂O₂ secretion at the single-cell level.

中文翻译：

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集成微流液滴传感器和金纳米团簇敏感检测单细胞分泌的H ₂ O ₂。

作为重要的信号分子，细胞外部分泌的过氧化氢（H ₂ O ₂）影响细胞迁移，免疫力产生和细胞通讯。在本文中，我们已经开发了一种与Au纳米团簇相结合的液滴微流控方法，用于灵敏检测单个细胞分泌的H ₂ O ₂。单细胞分泌的H ₂ O ₂隔离在微滴的超小体积（4.2 nL）中，可以引发辣根过氧化物酶– Au纳米团簇的剧烈荧光变化。我们已经证明了超高灵敏度（200–400 attomole H ₂ O ₂直接从单个细胞中测得）具有良好的特异性。它为研究单细胞水平H ₂ O ₂分泌的细胞间差异提供了有用的研究工具。